Marcel Duchamp is responsible for one of the definitive works of Twentieth Century art, the infamous and iconic Fountain, a urinal that the artist signed 'R. Mutt 1917' and exhibited in a gallery amid all manner of controversy and 'is it art?' debate. The work was undoubtedly a major moment in art history - it was voted the most influential artwork of the Twentieth Century in 2004 - and its influence can be seen in the works of Andy Warhol, Richard Wentworth and all of the YBA crew.
Duchamp himself was born in 1887 and his first works were largely Post-Impressionist in style with elements of Fauvism and Cubism. Controversy started with his attempt to exhibit the Cubist/Futurist work Nude Descending a Staircase. Duchamp withdrew the piece form the Salon des Independants and when it was eventually shown at the 1913 Armory show in New York it caused a scandal.
Following this, and influenced by Max Stirner's The Ego and Its Own, Duchamp sought to move away from an art based around aesthetics. In the 1910s he began work on his 'readymades' including Bicycle Wheel, a bicycle wheel on a stool, and later the infamous Fountain.
Duchamp was one of the key figures in the Dada movement, is vaguely associated with Surrealism and was a pioneer of kinetic art. In the '20s he gave it all up and played chess for a decade. He died in 1968, and along with Warhol and Picasso, is one of the major figures in art's development over the last 100 years.